oil and water

No replies to this topic
  • dave_v

Posted March 02, 2008 - 10:23 AM


I had not run the bike (01 yz426 with <100 hours) for three months, so I took it out for a quick spin around the block to get it warmed and check all the fluid levels before the riding season starts. Everything went fine until i popped the rad cap and saw the fluid had turned from green to brown. I drained the oil, which had zero hours on it, and it looks like there's water in the oil too.

So I search the archives, and the prevailing thought seems to be head gasket, followed by the base gasket and o-rings. I called the local Yamaha shop to see how much it would cost to fix a head gasket, and they suggest the following:

piston kit $150
cam chain $40
base/head gasket and o-rings etc $50
labor (4.5 hours @ $80/hr) $360

Since the engine has low hours, and has never eaten any oil, or every smoked, I was avoiding any valve work. So the total is about $600, which is not nearly as bad as I was thinking. First questions then:

1) does this seem like a reasonable parts list to solve the problem, and address other high wear items while its apart?
2) are the prices reasonable?
3) any other work/parts that would be worthwhile?

When I was talking with him about the mixing fluids, he said that he thought it might just be the water pump seals. I remember seeing a comment by greyracer that this was not possible since there are seals on both oil and coolant sides, and a weep hole to vent anything that got past either seal. Right?

Thanks guys!


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